Dust separating apparatus



Feb. 12, 1935. C SMlTH DUST SEPARAT ING APPARATUS Filed Feb. 25, 1935 5 Sheets-Sheet 1 INVENTOR ATTO RN EYS Feb. l2, 1935.

-J. c. sMlTH 1,991,337

DUST SEPARATING APPARATUS Filed Feb. 25, 1935 5 Sheets-Sheet? INVENTOR BY MQ y ATTORNEYS Feb. l2, 1935*. J. c. SMITH l 1 ,991y337 DUST SEPARATING APPARATUS Filed Feb, 25, 1935 y '3 Sheets-Sheet 3 Patented Feb. l2, 1.935

UNITED STATES PATENT OFFICE United States Electrical Tool Company,

Cin-

cinnati, Ohio, a corporation of `(lhio Application February 25, 193s, serial No. 658,605

5 claims.' (ci. isa-'17) This invention relates to apparatus for drawing olf dust laden air and separating the dust from the air, particularly in conjunction with grinding and polishing machinery. Operation of griding 5 Iand polishing machinery necessarily entails the creation ofla great amount of dust and abrasive particles from thesurface of the grinding wheel and from the parts being ground or polished which are thrown ol in the region of the grinding wheels and unless effectively collected and drawn ccreate a constantly unhealthy and uncomfortable environment and condition for the workmen. In view of this fact. suction apparatus has heretofore been designed for drawing off all dust and particle laden air from the region of the grinding wheels, but up to the present the development has involved a great deal of bulky equipment and separate power devices with the lack of eflicient separation and collection of the -0 dust so that the air could be discharged in dust free condition and, if desired, delivered back into the room.

It is the object of this invention to provide apparatus for drawing off separating. and collecting 5 dust and abrasive from the regions about grinding wheels and the like, which apparatus is highly eilicient, extremely compact and simple and is readily incorporated within the structure of the average grinder.

It is a further object to provide that the power driven element of the apparatus is driven directly from the power shaft of the grinding machine and that the suction chamber and connectiens are so associated and mounted within the framework of the machine as to be readily incorporated with no changes and to also provide,

within the confines of the grinding machine structure,- a conveniently emptied dust collecting chamber.

'10 Other objects and further advantages will be more fully apparent from a description of the accompanying drawings, in which:

Figure 1 is a rear view of a grinder illustrating Y the dust collecting and separating apparatus incorporated therewith.

Figure 2 is a sectional view taken on line 2-2, Figure 1. showing the arrangement of the apparatus within the interior of the grinder and l particularly illustrating the dust collecting chamber.

Figure 3 is a sectional view taken on line 3-3, Figure 2, illustrating the grinder and the relation of the dust collecting apparatus thereto.

Figure 4 is an end view of the grinder.

power shaft of the,

Figure 5 is a fragmentary view showing one end of the grinder in front view and illustrating a particular hood and conduit extending from a grinding wheel thereof.

The dust collecting and separating apparatus 5 incorporated in the present machine preferably receives its power from the grinding wheel shaft of the grinder and is embodied in the grinding machine so as tc make a compact unitary structure. In the particular grinder disclosed the 1 power is derived from an electric motor enclosed in the housing or casing framework 11 of the machine, which motor drives the main shaft 12 by a. pulley and belt connection. The particular' machine includes two grinding wheels 13, one at each extended end of the grinding wheel shaft 12.

Referring more specifically to the drawings, the hollow frame or casing-like body l1 of the machine has the grinding wheel shaft 12 disposed 20 through the upper part thereof and journalled in bearing brackets 14, 14, at each end of the machine.l

The grinding wheels 13 of conventional structure are fixed, one on each end of the shaft. The electric motor 10 is adjustably mounted on a pivoted motor base 15 and a belt 16 is extended between a pulley 1'? of the motor and a pulley 18 lixed on thev grinding wheel shaft. The rear side of the main casing or frame of the machine provides 30 an opening 19 which is covered by means of a vent plate 20 extending substantially entirely over the rear side of the frame and tted to the curvature thereof.

'I'he motor base consists of a plate of sutlicient width to provide for ample supporty for and attachment of the legs of the motor. This plate is mounted on a hinge or pivot rod 21 disposed across the machine toward the forward side thereof. The base plate includes an extension 22 pro- 40 truding through a slot 23 in the vent plate and providing an adjustable mounting for the rear end of the motor base. The extension 22 is disposed between adjustment blocks 24 loosely disposed on a screw rod 25 extending upwardly from a lower pivotal connection on apin 26 in lugs 27 of the main frame. The screw rod 25 loosely traverses the lug or extension 22 of the plate and the adjustable support blocks include convex inner ends engaging the ends of the opening through which the screw rod passes. These adjustment blocks are moved by circular or hand wheel elements or nuts 28 screwed on the rod. Thus by raising and lowering the rear end of the motor base, the motor base is swung on its pivot and the belt is tightened by varying the vdistance between the motor center and the grinding wheel shaft center. A

'I'he bearing parts for the grinding wheel shaft are of elongated form and are rigidly bolted to the frame. Each provides ball bearings 29 spaced apart by means of spacer sleeves 30. l The ends of the bearing brackets are sealed by means of packing rings 31.

Generally speaking the dust collecting and separating apparatus includes hoppers or guards 32 enclosing the grinding wheels, each having extended therefrom a conveyor or suction pipe 33 connected to the suction chamber 34. A suction element 35 is mounted in the chamber, which element separates the dust from the air directing the air out through an exhaust pipe 36 and the dust into a collecting chamber 37 supported within the hollow framework of the machine.

'I'he intake hoppers 32 are of sectional structure, one part 38 being rigidly fixed to the frame below the grinding wheel and the other part 39 being hinged to the first and extended about the grinding wheel. The lower element is' mounted by means of angle iron strips 40 bolted to and extending from the side of the frame and provides a vertically elongated forward opening below the grinding wheel.

The upper section or cover 39 forming a. continuation of this opening is hinged to swing upon and extend the open upper end of the hopper. 'I'he upperelement is 'formed to fit .about the grinding wheel, leaving the forward portion of the wheel clear for application of work and swings down rearwardly to a position of rest as shown in dot and dash lines, Figure 4, on the cross piece of a rail 41 of U-shape having its arms fixed to the lower element and including angle iron lengths 418L along the arms for reenforcing the upper edge of the lower hopper section.

r The lower edge of the cover 39 includes a doublegrooved sealing strip 42 fixed thereto, the inner groove 43 thereof adapted to lie upon the upper edges of the hopper lower section and the outer groove carrying felt sealing strips 44 lying against the sides of the hopper. Baffie plates 45 extend downwardly at varied angles from the mouth of the hopper lower section to the rear or conveyor pipe connection thereto for receiving and directing the abrasive particles into the suction or conveyor pipe 33.

Accordingly it will be 'observed that there is an intake mouth extending from the top of the grinding wheel almost to the floor line and that a wide area or region around the grinding wheel is subjected to the suction action. The suction pipes or conveyor tubes 33 extending from the hoppers are joined at the rear of the machine as at 46 (see Figure 1) and enter the dust co1- lecting or suction chamber 34 axially.

'I'he chamber or casing 34 is mounted within and attached to the framework of the machine. The shaft 12 on which the grinding wheels are mounted axially traverses the conveyor or suction line as it connects to the suction chamber. The dust collecting or suction chamber is formed of two circumferentially abutting pieces and these elements. are secured together and the assembly screwed to an offset portion of the framework by means of screws 48. At the point of the fan unit the framework for the casing of the machine is enlarged and formed on the radius to provide ample space for theunit.

The suction fan and dust separating element 35 is keyed to the shaft of the machine within the suction chamber 34 and includes a multiplicity of blades 49 or vanes secured to a disc. These blades as observed in end view of the device are curved and include radially extended tips 50. The air outlet or discharge conduit 36 for the suction unit extends substantially tangentially from the casing and maybe directed upwardly or at any desired angle. y

Adjacent the path of movement of the blades and particularly the tips is a dust outlet openingV 51 extended downwardly .and continued through the medium of a dust discharge tube 52, A dust collecting chamber casing or compartment 37 is fixed to the lower end of the suction casing on extended feet 53 thereof, the dust container being disposed within the framework of the machine with the exception of a rearwardly extended clean-out snout 54 which includes a hinged and latched clean-out closure 55. The dust discharge tube 52 extends into this dust collection chamber.

An opening 52a is provided in the suction chamber casing for air circulation back into the suction casing from the dust collection compartment. The upper part of the chamber is formed as at 56 whereby ample clearance is provided for 'connection of the collector or intake manifold pipe 57 to the suction device. The rear normally open side of the framework is closed by means of the vent plate 20, which includes`openings 58, 59, for tting the plate about .the snout and the inlet pipe respectively, and a further cover 60 is provided fitting about the outlet of the suction device and covering the circumferential clearance ,slot 61 which permits adjustable disposition of the outlet pipe.

Thus all abrasive emanating from the grinding wheels is conveyed into the machine and separated i from the air in a self-contained system, the air being delivered from the machine in dust-free condition. I

Having described my invention, I claim: 1. In a dust collecting apparatus adapted toI be included in a grinding machine including grind` ing wheels, a suction fan driven by the grinding machine, a suction casing surrounding said fan, dust collector pipes extending from the region of the grinding wheels tothe suction casing, an air discharge pipe extending tangentially from the suction casing at one side of the suction fan, a dust exhaust tube extending substantially radially from the suction casing, and a dust collector pan for receiving the dust from said dust discharge tube.

2. A dust collecting apparatus for the grinding wheels of a grinding machine, comprising, a machine frame, a dust collector compartment within said frame, a dust separating suction fan enclosed within a compartment of said -machine frame, said latter compartment including an air discharge duct offset from said fan and communicating with the atmosphere and a dust discharge tube extending to said dust collector compartment, and a dust-laden air collector conduit extending from the region of the grinding wheel to said fan compartment.

3. A dust collecting apparatus for a grinding machine including a hollow frame, a grinding wheel shaft, and grinding wheels thereon; a dust separating suction fan fixed on the shaft, a suction casing surrounding said fan and xed within the hollow frame of the machine and traversed by Said shaft, collector pipes extending from the grinding Wheels and having Va manifold pipe connection to the suction casing axially thereof, an air discharge tube extending from the suction casing at one side of the fan. and a dust discharge tube extending substantially radially from the suction casing directly adjacent the fan.

4.. In a dust separating apparatus for a grinder frame of the grinder about the fan, an exhaust conduit extending from the suction chamber casing tangentially thereof and at one side of the suction fan, a collector pipe extending from each grinding wheel including a hopper enclosing the 'region about the grinding wheel and to a substantial distance below the grinding wheel, a manifold pipe? to which said collector pipes are connected, said manifold pipe extending into the machine frame and connected to the suction chamber casing axially, a 'dust discharge tube of the type having a hollow frame and includ-- ing grinding wheels and a power shaft for said i wheels, a suction fan and dust separating element ilxed on the shaft of the grinder,` a suction chamber casing mounted within the hollow frame of the grinder about the fan, an exhaust conduit extending from the suction chamber casing, a collector pipe extending from each grinding wheel including a hopper enclosing the region about the grinding wheel, said collector pipes extending into the machine frame and connected tothe suction chamber casing, a dust discharge tube extending from the suction chamber casing, and a dust collection pan iixed within the machine frame.

JOHN C. SLU'IH.` 

